Removing some unused dependencies

Identified with depcheck

package.json

@@ -8,15 +8,12 @@
     "node": ">=12.13.0"
   },
   "dependencies": {
-    "@blueprintjs/core": "^3.39.0",
     "@material-ui/core": "^4.10.1",
     "@material-ui/icons": "^4.9.1",
     "axios": "^0.21.1",
     "elasticlunr": "^0.9.5",
     "gatsby": "^3.0.4",
-    "gatsby-plugin-flexsearch": "^1.0.3",
     "gatsby-plugin-netlify-cms": "^5.0.0",
-    "gatsby-plugin-offline": "^4.0.0",
     "gatsby-plugin-react-helmet": "^4.0.0",
     "gatsby-plugin-react-svg": "^3.0.0",
     "gatsby-source-filesystem": "^3.0.0",
@@ -33,7 +30,6 @@
     "react-helmet": "^5.2.1",
     "react-highlight-words": "^0.16.0",
     "react-icons": "^3.10.0",
-    "react-responsive-carousel": "^3.2.7",
     "react-slick": "^0.25.2",
     "remark-html": "^13.0.1",
     "remark-preset-lint-recommended": "^5.0.0",